If you are logged into a CentOS Linux system, there are a few ways you can determine the version of CentOS running on the system from a command-line interface (CLI), i.e., a shell prompt.
In the /etc directory, there should be a
/etc/centos-release file containing information on the version
of CentOS.
$ ls -l /etc/*elease -rw-r--r-- 1 root root 27 Mar 28 2017 /etc/centos-release -rw-r--r--. 1 root root 152 Nov 25 2013 /etc/lsb-release lrwxrwxrwx 1 root root 14 Apr 20 2017 /etc/redhat-release -> centos-release lrwxrwxrwx 1 root root 14 Apr 20 2017 /etc/system-release -> centos-release $ cat /etc/*elease CentOS release 6.9 (Final) LSB_VERSION=base-4.0-amd64:base-4.0-noarch:core-4.0-amd64:core-4.0-noarch:graphi cs-4.0-amd64:graphics-4.0-noarch:printing-4.0-amd64:printing-4.0-noarch CentOS release 6.9 (Final) CentOS release 6.9 (Final) $
To just see the version number, you can use one of the grep commands below.
$ grep -oE '[0-9]+\.[0-9]+' /etc/redhat-release 6.9 $ grep -oE '[0-9]+\.[0-9]+' /etc/centos-release 6.9 $
If CentOS 7 is installed, you can also check the contents of
/etc/os-release.
$ cat /etc/os-release NAME="CentOS Linux" VERSION="7 (Core)" ID="centos" ID_LIKE="rhel fedora" VERSION_ID="7" PRETTY_NAME="CentOS Linux 7 (Core)" ANSI_COLOR="0;31" CPE_NAME="cpe:/o:centos:centos:7" HOME_URL="https://www.centos.org/" BUG_REPORT_URL="https://bugs.centos.org/" CENTOS_MANTISBT_PROJECT="CentOS-7" CENTOS_MANTISBT_PROJECT_VERSION="7" REDHAT_SUPPORT_PRODUCT="centos" REDHAT_SUPPORT_PRODUCT_VERSION="7" $
For version 7 and earlier versions, You can also use a
RPM Package Manager (RPM) command, rpm --eval
'%{centos_ver}' or rpm --eval '%{centos}' to see just the
major version number or rpm --query centos-release to see the
major and minor version information.
$ rpm --eval '%{centos_ver}'
6
$ rpm --eval '%{centos}'
6
$ rpm --query centos-release
centos-release-6-9.el6.12.3.x86_64
$If the lsb_release
utility is installed, you can also use it to
determine the version number. The utility is part of the
redhat-lsb-core package, which you can install with
yum install redhat-lsb-core.
$ lsb_release -d Description: CentOS release 6.9 (Final) $ lsb_release -r Release: 6.9 $
If the hostnamectl utility, which is provided by the systemd package, is installed, you can also use it to see the version number of CentOS and whether the system has a 32-bit or 64-bit architecture.
$ hostnamectl | grep "Operating \| Architecture"
Operating System: CentOS Linux 7 (Core)
Architecture: x86
$